surfshark.sh

#!/bin/sh

surfshark_username="${SHARK_USERNAME:-email@example.com}"
surfshark_password="${SHARK_PASSWORD:-password}"

login_payload_template='{"username":"%s","password":"%s"}'
login_payload=$(printf "$login_payload_template" "$surfshark_username" "$surfshark_password")

echo "Initialising Surfshark SmartDNS Updater v2.0"

ipfile="/tmp/ss_ipfile.dat"
old_ip=""
new_ip=`curl -s 'https://api.ipify.org'`

if [ -f "$ipfile" ]
then
    old_ip=`head -n 1 $ipfile`
fi

if [ "$old_ip" = "$new_ip" ]
then
    echo "Old/New IP are the same, no update needed"
    exit 0
fi

echo "Logging in with username $surfshark_username"

login_request=`curl -s -X POST "https://api.surfshark.com/v1/auth/login" -H "Content-Type: application/json" --data $login_payload`
if [ -z "$login_request" ]
then
    echo "Login failed. Check your username or password"
    exit 1
else
    bearer_token=`echo $login_request | awk -F "[,:}]" '{print $2}' | tr -d '"'`
    echo "Logged in successfully"
fi

update_request=`curl -s -X POST "https://api.surfshark.com/v1/server/smart-dns" -H "Authorization: Bearer $bearer_token"`
user_ip=`echo $update_request | awk -F "[,:}]" '{print $4}' | tr -d '"'`

if [ "$user_ip" = "Invalid JWT Token" ]
then
    echo "Update failed - Payload $update_request"
    exit 1
else
    echo $new_ip | tee $ipfile
    echo "Updated SmartDNS IP to $user_ip"
fi